Best time to fly Fort Lauderdale to Chicago

Every month pooled across the years on record, so "July" means July generally rather than one particular July. Full FLL to ORD record →

Best month

September

84.9% on time · 206 flights

Worst month

March

51.8% on time · 440 flights

Month Flights On time Cancelled When late, by
January 384 63.9% 2.34% 65 min
February 356 69.4% 0.84% 84 min
March 440 51.8% 5.45% 107 min
April 325 64.6% 2.77% 94 min
May 229 78.3% 0% 62 min
June 202 73.4% 0.99% 97 min
July 211 71.2% 1.9% 110 min
August 203 76.9% 0.49% 116 min
September 206 84.9% 0.49% 81 min
October 219 76.3% 0% 39 min
November 287 71.5% 1.74% 103 min
December 360 68.9% 0.56% 75 min

What a seasonal pattern can and cannot tell you

Months differ for reasons that repeat — summer thunderstorms in the American interior, winter fog and de-icing in northern Europe, school holidays filling every seat and leaving no slack in the schedule. Those are real and they come back each year.

What the pattern cannot do is forecast a particular flight. A quiet month has late days and a bad month has punctual ones. Treat this as a way to choose between two dates you are indifferent about, not as a promise.